Definition: You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.
Input: Question: Pipe A can fill a tank in 10 hours. Due to a leak at the bottom, it takes 15 hours for the pipe A to fill the tank. In what time can the leak alone empty the full tank?

 Option A: 76

 Option B: 84

 Option C: 56

 Option D: 75

 Option E: 30

Option E